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Create a 100Mb file for testing transfer speeds

 Author
Author
Sam McGeown
Steely-eyed missile man
Warning: This article is now 18 years old! It is highly likely that this information is out of date and the author will have completely forgotten about it. Please take care when following any guidance to ensure you have up-to-date recommendations.

We have a Bonded ADSL solution for our servers to provide the necessary upstream transfer speeds for the applications we host. We have bonded ADSL because our exchange still doesn’t support SDSL, and a leased line is overkill. Theoretically, we should have 28.1 Mbps download and 3.2Mbps upload - what I am actually seeing is about 1.7Mbps down and 1.9Mbps up. I have tested this on various servers, over various times and file sizes, there is no doubt that the performance is POOR.

Anyway, on to my point. I wanted to create a file that was exactly 100MB to test transfer speeds. Windows XP, Vista, 2003 and 2008 all have a command line utility called FSUTIL.exe which has a subset of commands to manipulate files, with which you can create a file that is exactly 100MB…like so:

FSUTIL FILE CREATENEW 100MBTest.mdb 1048576

Usage: FSUTIL FILE CREATENEW

\[Filename\]

\[Size in bytes\]

 Nice!